The flight systems of modern commercial aircraft are operated extensively under the control of one or more computers. For example, the Boeing 737-300 and 757/767 commercial aircraft utilize a flight management computer in which a flight path profile from takeoff to landing may be stored. Flight commands such as aircraft heading, altitude, and altitude rate are generated within the flight management computer and are fed to an autopilot system which manipulates the aircraft flight control surfaces to cause the aircraft to fly a path corresponding to the stored flight path profile.
In order for the integrated system of the autopilot system and the flight management computer to function properly, the computer must generate commands to which the autopilot system is responsive. Integration of the autopilot system with a computer requires an interface controller which generates commands as a function of a stored flight profile to cause the autopilot to respond in the desired manner.